Open sign



FIG. 1 is an isometric view of an open sign incorporating my new design in a first, horizontal configuration, wherein the portions illustrated in broken lines form no part of the claimed design throughout the drawing figures;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a right end elevation view thereof; and,

FIG. 7 is a left end elevation view thereof. 

The ornamental design of an open sign, as shown and described. 